LS1 Aftermarket MAF Sensor, Water Pump Install - Go With The Flow

Will two simple mods free up more LS1 power?

Step By Step

The Meziere electric water pump is a functional work of art. The CNC-machined pump (part No. WP319, $632) includes stainless steel hardware, showed up with everything save for a small-block Chevy thermostat, and is available polished, silver, red, black, or in our case, blue. This street pump weighs in at only 15 pounds and carries a 55 gallon-per-minute rating.

Also included with all of the installation hardware and heater hose fittings was Meziere's new billet water inlet (part No. WN0019, $110), which complements the pumps and is available in all of the same colors.

Since the inception of GMHTP's LS1 project car, we've cut a full second off its ET (13.36 to 12.36), added 6 mph (103 to 109) to the trap speed, and added 55 horses and 48-foot pounds to the wheels. Up to this point we've had great luck assaulting the '99 T/A with a bevy of bolt-ons, hooking it up with trans mods and a converter, and giving it just enough traction to drop ETs without shredding the stock, 3.23-geared rearend. Of course, there's no way of telling when this 7.5-inch weakling is going to bow out in spectacular fashion; we'll deal with the sorry-assed 10-bolt when the time comes.

Regarding external engine mods, the bolt-on flood has slowed to a trickle; there were only a few more that we wanted to test before moving on to bigger and better things.

Three of those mods, an electric water pump, a larger mass air meter, and an aftermarket throttle body, have enjoyed internet infamy for quite some time. The jury is still out on whether these "performance enhancing" LS1 mods do anything positive--so we wanted to dyno test them to find out for sure. Unfortunately a supposedly kick-ass throttle body wasn't ready in time for testing, so then there were two.

So for this go-around, we put these LS1 components to the test: a Meziere electric water pump and an SLP 85mm mass air meter. Neither are absolutely necessary at our approximate 350-rwhp level, but may prove helpful in the days ahead. Three critical areas will be measured with the help of SuperFlow components: the dyno will record changes in rear-wheel power and any changes in coolant temperature, and the flow bench will measure any changes in airflow between the OEM MAF and the 85mm unit. Let's get going.